Conventional plastic scintillator optics generally comprise a bulk plastic material that is preferably transparent to ultraviolet or visible light generated by incident ionizing radiation of types to be detected using the scintillator device. The most common of such materials include polystyrene (PS) and polyvinyl toluene (PVT) owing to the well-known and desirable optical properties of such materials in the context of use in a scintillation radiation detector.
However, as is also known in the art, such conventional materials tend to degrade over time with exposure to environmental conditions such as water vapor and/or significant temperature changes. Most notably, and as shown in FIGS. 1A-1C and 2A-2B, a conventional detector may be substantially transparent and suitable for use in detecting radiation of interest following fabrication (FIG. 1A), but following exposure to undesirable environmental conditions surface defects may arise via a process known as “crazing” (FIGS. 1B, 2A) and even more detrimentally defects may form in the bulk volume of the optic, a phenomenon known as “fogging” (FIGS. 1C, 2B). Each type of defect causes scattering of light incident upon the surface of and/or propagating through the detector bulk, undesirably reducing the sensitivity of the detector and ultimately defeating the ability to detect the radiation of interest.
Accordingly, conventional wisdom is to avoid exposing the detector to the undesirable environmental conditions, thereby avoiding the reduction or loss of detection capability. However, this precludes the use of such detectors in environments where radiation detection may be necessary, particularly via prolonged observation over a long period of time.
In addition, there is no currently-known method for restoring the functionality of detectors exhibiting crazing and/or fogging.
Accordingly, it would be useful to provide systems and techniques that minimize or eliminate occurrence of crazing and fogging within plastic scintillation radiation detectors exposed to environmental conditions known to cause such defects, as well as to reverse the negative impact caused by such exposure.